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I still say the donor vehicle should not be running when you hit the starter on the dead engine. Some alternators may have short circuit protection, but unless you know for certain, the donor engine should be off. Why risk your alternator for nothing. They are expensive. You can run the donor engine to charge the other battery for a while if needed.

I think using the idea for a CHARGE only might be feasible. Plug into running bike and connect to weak battery bike for a while. If wires show signs of getting warm disconnect immediately. Also have inline fuse that blows and limit to 5 amps.

Hooked directly to the battery of my truck it wouldn't even turn over the PB (I didn't expect it to). After "charging" the batteries on the PB (there are three) for about ten minutes we got enough of a surface charge to start the diesel. The driver of the PB hit the starter before I could unhook the jumper cable to my truck, but there doesn't appear to be any problem.

Of course we're not talking 12 & 14ga wire here either.

"It is what you discover, after you know it all, that counts." _ John Wooden

A few months ago, I saw a set of jumper cables on line that were kind of neat.
They had a beefy harness that replaced the one from your standard micro battery charger and a set of cables that plug into it. One harness for both charger and cables The mfgr. was very clear that harness that comes with a battery charger is not made with heavy enough wire. Not for $104.00 either!

The ford alternator is question is the 2G model, from like mid 80 to early 90's and it is not the diodes with it. they ran all the alternator current of up to 80 amps thru 2 spade connectors, when they get loose, there is smoke and often fire. The part that flames is the rectifier, that is where they put the diodes. Only an idiot would run alternator current thru a 1/4 inch fast on. What is on the diode board you say???

Alternators are current limited, mostly they will not burn up if OE. Once they are rebuilt with Chinese components all bets are off. With the hood up there is cool enough temperatures most all of them will never fry. This is also true with the Bosch alternators the later BMW use.

Permanent magnet alternators are another thing, many of them are under engineered, so you would not want to load to maximum for long.